Book to explain facts of life?

dd1 is 10 and doesn't know about sex - I can't even get her to ask questions. She is very, very naive and sweet but fgs, next year she'll be in secondary school.

Is there a book about the facts of life? That I can read? No good getting her a book just for her to read because she won't read it. She will place it on her bed whilst she plays with her ponies, like all her other books.

I need her to know now. I need a book, because I cannot just sit on the end of her bed without some kind of safety net and launch into a talk about penises.

'Let's Talk About Sex' - R Harris (I think). My 10 year old DD's have had this book in their room for over a year now. They resist any attempt for me to talk to them (although we went through puberty etc together a couple of years ago) but I know they have been reading this book. I think they know it all now anyway - they are doing this at school at the moment.